fix(acm): safe array expansion in fast-forward script

[dislbenn]

Fixes unbound variable error causing periodic job failure.

Problem

Periodic job periodic-ci-stolostron-acm-config-main-fast-forward failed with:

/bin/bash: line 1447: SKIPPED_NO_ACCESS: unbound variable

Failed run

Root Cause

Script uses set -uo pipefail. Array length checks like ${#ARRAY[@]} fail when arrays are empty with set -u.

Fix

Use safe parameter expansion ${#ARRAY[@]:-0} for all array length checks:

• SKIPPED_NO_ACCESS
• FAILED_FASTFORWARDS
• FAILED_TEKTON
• CLEANED_BRANCHES

Testing

Fix allows summary section to complete even when arrays are empty.

🤖 Generated with Claude Code

Overview

This PR fixes a recurring failure in the ACM (Advanced Cluster Management) CI infrastructure by correcting a Bash script error in the fast-forward synchronization workflow used by the stolostron/acm-config CI job.

Problem

The periodic job periodic-ci-stolostron-acm-config-main-fast-forward was failing with "/bin/bash: line 1447: SKIPPED_NO_ACCESS: unbound variable". The fast-forward script runs with strict Bash options (set -uo pipefail), and checks like ${#ARRAY[@]} can cause an unbound-variable exit when arrays are unset under set -u.

Solution

The fast-forward step script (ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh) now ensures the tracking arrays are defined before they are inspected. The arrays FAILED_FASTFORWARDS, FAILED_TEKTON, SKIPPED_NO_ACCESS, and CLEANED_BRANCHES are initialized as empty arrays (ARRAY=()) so length checks and summary reporting no longer trigger unbound-variable errors. The change also removed incorrect use of default operators in the earlier commit; overall the script now safely handles empty/unset arrays under set -u.

Impact

With these changes the periodic fast-forward job can complete its summary and finish successfully even when no failures occur. This stabilizes the stolostron/acm-config fast-forward workflow used by OpenShift CI to keep ACM repository branches and Tekton/config updates synchronized.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository YAML (base), Central YAML (inherited)

Review profile: CHILL

Plan: Enterprise

Run ID: 8c79b6af-68ef-4105-8b09-510fd70eccd3

📥 Commits

Reviewing files that changed from the base of the PR and between 43e834d and 8b45401.

📒 Files selected for processing (1)

• ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh

✅ Files skipped from review due to trivial changes (1)

• ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh

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Walkthrough

The Bash script ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh now explicitly initializes tracking arrays (FAILED_FASTFORWARDS, FAILED_TEKTON, SKIPPED_NO_ACCESS, CLEANED_BRANCHES) to empty arrays instead of using declare -a, preventing unbound-variable failures under set -u.

Changes

Array initialization fix

Layer / File(s)	Summary
Initialization ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh	Replaces declare -a array declarations with explicit empty-array assignments (e.g., FAILED_FASTFORWARDS=()) so arrays exist when set -u is enabled.
Usage / Reporting ci-operator/step-registry/ocm/ci/fastforward-multiple/ocm-ci-fastforward-multiple-commands.sh	Existing final-summary and listing logic that checks array lengths or iterates arrays now operate on defined arrays, avoiding nounset errors.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~4 minutes

🚥 Pre-merge checks | ✅ 12

✅ Passed checks (12 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly addresses the main change: initializing arrays safely to prevent unbound variable errors in the fast-forward script.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Stable And Deterministic Test Names	✅ Passed	The custom check for Ginkgo test names applies only to Go test files. This PR modifies only a bash script with no test title definitions, making the check not applicable.
Test Structure And Quality	✅ Passed	Custom check is for Ginkgo test code quality, but PR only modifies a bash shell script for CI operations. No Ginkgo tests present—check not applicable.
Microshift Test Compatibility	✅ Passed	This PR modifies only a bash shell script to fix array initialization issues. No Ginkgo e2e tests or Go test code is added, so the MicroShift Test Compatibility check is not applicable.
Single Node Openshift (Sno) Test Compatibility	✅ Passed	This PR modifies a bash CI operator script, not Ginkgo e2e tests. The custom check applies only to new Ginkgo e2e test additions, which are not present in this PR. Check is not applicable.
Topology-Aware Scheduling Compatibility	✅ Passed	PR modifies a bash CI/CD script only, with no Kubernetes manifests or scheduling constraints. Check not applicable.
Ote Binary Stdout Contract	✅ Passed	PR modifies only a bash shell script. The OTE Binary Stdout Contract check applies to Go test binaries with JSON stdout. This bash script is not a test binary and is not subject to this check.
Ipv6 And Disconnected Network Test Compatibility	✅ Passed	No Ginkgo e2e tests are present. The PR only modifies a bash shell script (ocm-ci-fastforward-multiple-commands.sh) for CI operations, not test code. The custom check is not applicable.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

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[dislbenn]

/pj-rehearse periodic-ci-stolostron-acm-config-main-fast-forward

[openshift-merge-bot]

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[dislbenn]

/pj-rehearse periodic-ci-stolostron-acm-config-main-fast-forward

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[dislbenn]

/pj-rehearse periodic-ci-stolostron-acm-config-main-fast-forward

[dislbenn]

/pj-rehearse periodic-ci-stolostron-acm-config-main-fast-forward

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[ngraham20]

/lgtm

[mark-nc]

/lgtm

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dislbenn, mark-nc, ngraham20

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[dislbenn]

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